1. Field of the Invention
The present invention relates to a coupling mechanism, and more particularly to a coupling mechanism of a socket wrench extension.
2. Description of the Prior Art
A typical locking socket wrench extension is disclosed in U.S. Pat. No. 4,781,085 to Fox, III and comprises a locking bolt slidably engaged in the axial bore of the extension, a thumb lever for moving the locking bolt and a ball actuated by the locking bolt to engage with the sockets. Both the thumb lever and the locking bolt comprise a rather complicated configuration that is not good for manufacturing purposes. In addition, a cover is required to be secured to the end portion of the axial bore for preventing the ball from disengaging from the extension. However, it will be difficult to secure the cover in place.
Another typical wrench extension and socket coupler is disclosed in U.S. Pat. No. 4,962,682 to Rose et al., and comprises a longitudinal passageway for receiving a number of balls and a lateral passageway for receiving an actuator and a spring therein. The balls and the actuator may not easily assembled in the extension. The actuator should be depressed inward of the lateral passageway by a post means before the opening of the lateral passageway is formed with an annular crimp for retaining the actuator in place. It will be difficult to depress the actuator and to form the annular crimp simultaneously.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional socket wrench extensions.